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+==========================
+reclass configuration file
+==========================
+|reclass| can read some of its configuration from a file. The file is
+a YAML-file and simply defines key-value pairs.
+
+The configuration file can be used to set defaults for all the options that
+are otherwise configurable via the command-line interface, so please use the
+``--help`` output of |reclass| (or the :doc:`manual page <manpage>`) for
+reference. The command-line option ``--nodes-uri`` corresponds to the key
+``nodes_uri`` in the configuration file. For example::
+
+  storage_type: yaml_fs
+  pretty_print: True
+  output: json
+  inventory_base_uri: /etc/reclass
+  nodes_uri: ../nodes
+
+|reclass| first looks in the current directory for the file called
+``reclass-config.yml`` (see ``reclass/defaults.py``) and if no such file is
+found, it looks in ``$HOME``, then in ``/etc/reclass``, and then "next to" the
+``reclass`` script itself, i.e. if the script is symlinked to
+``/srv/provisioning/reclass``, then the the script will try to access
+``/srv/provisioning/reclass-config.yml``.
+
+Note that ``yaml_fs`` is currently the only supported ``storage_type``, and
+it's the default if you don't set it.
+
+Adapters may implement their own lookup logic, of course, so make sure to read
+their documentation (for :doc:`Salt <salt>`, for :doc:`Ansible <ansible>`, and
+for :doc:`Puppet <puppet>`).
+
+.. include:: substs.inc